Many passenger vehicles now incorporate an integrated communication system. A Vehicle Communication Unit (VCU) used in conjunction with a Wide Area Network (WAN) such as a cellular telephone network or a satellite communication system allows for a variety of fee-based subscription services to be provided in a mobile environment. One such service provides for the use of a wireless phone within the vehicle. Users of these services find them convenient and at times a lifesaver in emergency situations.
One drawback to these fee-based subscription services, however, is the subscription cost which, at times, can be quite high. The cost of a plan may be based on many factors. The cost may be based on such factors as, for example, the total number of months duration of the plan, the number of minutes allowed per month, and the time of day a call is placed. Fortunately, service providers have a wide variety of plans available to suit most consumers' budgets.
A problem arises, though, when the subscriber uses the cellular phone for more than the amount of minutes allotted for a particular billing cycle. Depending on the service provider and other billing factors, the cost for these additional minutes can be very high. For example, a service provider may offer a plan where the cost is under one cent per minute. However, the cost per minute over the plan limit may be twenty-five cents or more. For most situations staying within the allotted number of minutes is not a problem. However, the probability of incurring additional fees is high for those who may travel extensively or who use the cellular phone for work. Excessive fees may also be a problem for parents that provide a cellular phone to their talkative children.
Some cellular phone providers offer inconvenient solutions to these problems. One solution provided is a prepaid cellular phone with a finite number of minutes, that upon their use the phone will not function. Another option is a calling card, also with prepaid minutes. Calling cards provide an inconvenient solution due to the requirement that the user must input a long string of digits that corresponds to the calling card and then the telephone number of the party they are trying to contact. Further, calling cards are easily lost or misplaced.
It would be desirable, therefore, to provide a system and method for replenishing calling units to a cellular phone that overcomes these and other disadvantages.